Ovarian activities of the West African dwarf goat (Capra hircus) during oestrus

Ovarian activity was studied by laparotomy of 9 adult nulliparous goats in which oestrus was synchronized. Ovulation occurred in animals operated on 20-48 h from the onset of sexual receptivity. There was a mean ovulation rate of 1.57 ova per doe and the right and left ovaries had similar follicular activity in relation to sizes of follicles and ovulations.     

Adiponectin multimers and metabolic syndrome traits: relative adiponectin resistance in African Americans

African Americans (AAs) tend to have lower total adiponectin levels compared to European Americans (EA); however, it is not known whether race affects adiponectin multimer distribution and their relationships to metabolic traits. We measured total adiponectin, high molecular weight (HMW), low molecular weight (LMW) (i.e., hexamer), and trimer adiponectin in 132 normoglycemic premenopausal women (75 AAs, 57 EAs), together with measures of total and abdominal fat, plasma lipids, insulin sensitivity (S(i)), and genetic admixture estimates. We found that lower total adiponectin in AAs was explained by reduced LMW, and trimer forms because levels of HMW did not differ between races. In EAs, HMW was highly correlated with multiple metabolic syndrome traits. In contrast, the LMW and trimer forms were most highly correlated with metabolic traits in AAs, including abdominal adiposity, lipids, and S(i). At similar levels of visceral adiposity, AAs exhibited significantly lower LMW adiponectin than EAs. Similarly, at comparable levels of HMW and LMW adiponectin, AAs were more insulin resistant than their EA counterparts. In conclusion, (i) serum adiponectin is lower in AAs predominantly as a result of reduced concentrations of LMW and trimers multimeric forms; (ii) LMW and trimer, not HMW, are most broadly correlated with metabolic traits in AAs. Thus, HMW adiponectin may exert less bioactivity in explaining the metabolic syndrome trait cluster in populations of predominant African genetic background.     

Evolution in indigenous west African rice

The genus Oryza contains two cultivated species,O. sativa L., the Asiatic rice, andO. glaberrima Steud. which is limited to Africa. Despite much taxonomic work on the relationships of the wild species of the genus, they are still imperfectly known and there has not been unanimous agreement on nomenclature. Most of the species group into complexes the delimitation of which is a matter of opinion. This paper presents results from experimental work, and a theory for the evolution of African cultivated rice is put forward based on taxonomic studies.     

Factors affecting placental traits and relationships of placental traits with neonatal behaviour in goat

The relationships between placental characteristics and litter weight, factors affecting these characteristics, and the relationship between these characteristics and neonatal behaviour of goat kids were investigated in this study. The study was carried out over three consecutive years and animal material consisted of total 152 Turkish Saanen goats and their 230 kids. The results of the study demonstrated that there were positive correlations between litter weight (LW), cotyledon number (CN), placental weight (PW) (r=0.64 and 0.76, P<0.01), but there was negative correlation between LW and cotyledon density (CD) (r=-0.42, P<0.01). CD was negatively correlated with PW (r=-0.61, P<0.01). CN and PW were influenced by the parity of doe, birth type-sex combination, buck within years and year of the study. On the other hand, parity and birth type-sex combination had no effect on PE (P>0.05), but buck within year affected placental efficiency (P<0.01). CD was only influenced by the parity of doe (P<0.01). Duration of birth (D) was not significantly related with CD, but if CD declined, it prolonged (r=-0.23, P>0.05). There were strong relationships between CD and birth-to-standing (B-St), and CD and birth-to-suckling (B-Su) (r=-0.42 and -0.51, P=0.01 and P<0.01).The results of the present study have shown similarities to the findings of the studies in sheep. Further studies are required to investigate the basis of the relationship between CD and neonatal behaviour.     

Novel polymorphisms of goat growth hormone and growth hormone receptor genes and their effects on growth traits

In this study, the polymorphisms of growth hormone (GH) gene 5' promoter region and intron 8, exons 4 and 10 of growth hormone receptor (GHR) gene were analyzed in Xinong Saanen goats (SG) and Boer goats (BG). Two alleles (A and B) and three genotypes (AA, AB and BB) were detected at P1 locus of GH gene, and two alleles (G and T) and two genotypes (GG and GT) were detected at P4 locus of GHR gene by PCR-SSCP analysis. In addition, two single nucleotide polymorphisms (SNPs)-A73C (P1 locus) and G114T (P4 locus), were identified by DNA sequencing. The frequencies of alleles A and B in the two goat breeds were 0.61-0.62, and 0.39-0.38, respectively, and the frequencies of alleles G and T in the two goat breeds were 0.82-0.86, and 0.18-0.14, respectively. The SNP loci were in Hardy-Weinberg disequilibrium in both goat breeds (P<0.05). Polymorphisms of GH and GHR genes were shown to be associated with growth traits in BG breed. AA and GG genotypes were associated with superior growth traits in 1-, 2- and 3-month old individuals. Hence, AA and GG genotypes are suggested to be a molecular marker for superior growth traits in BG breed.     

Combined effects of four SNPs within goat PRLR gene on milk production traits

Xinong Saanen (SN, n = 323) and Guanzhong (GZ, n = 197) goat breeds were used to detect single nucleotide polymorphisms (SNPs) in the coding regions with their intron–exon boundaries of prolactin receptor (PRLR) gene by DNA sequencing, primer-introduced restriction analysis-polymerase chain reaction (PIRA-PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP). Four novel SNPs (g.40452T > C, g.40471G > A, g.61677G > A and g.61865G > A) were identified. The g.61677G > A and g.61865G > A SNPs caused amino acid variations p.Ser485Asn and p.Val548Met, respectively. Both g.40452T>C and g.40471G>A loci were closely linked in SN and GZ goat breeds (r² > 0.33). In addition, there was also a close linkage between g.61677G>A and g.61865G>A loci in both goat breeds. Statistical results indicated that the g.40452T > C, g.61677G > A and g.61865G > A SNPs were significantly associated with milk production traits in SN and GZ breeds. Further analysis revealed that combinative genotype C1 (TTAAGGGG) was better than the others for milk yield in SN and GZ goat breeds. These results are consistent with the regulatory function of PRLR in mammary gland development, milk secretion, and expression of milk protein genes, and extend the spectrum of genetic variation of the caprine PRLR gene, which might contribute to goat genetic resources and breeding.     

Barley yellow dwarf virus infectivity of alate aphid vectors in west Wales

Live trapping at 0.9 m of alate aphid vectors of barley yellow dwarf virus (BYDV) at Aberystwyth from 1970 to 1979 showed that ten species transmitted the virus to oat test plants. Conversion of percentage infective at 0.9 m to numbers infective based on continuous trapping at 1.2 m showed Rhopalosiphum padi and R. insertum to be the main vector species in most years, whilst Metopolophium dirhodum and Sitobion auenae were normally of minor importance. The data obtained suggest that epiphytotics of BYDV in autumn-sown cereals were caused by numerous infective vectors flying late in the year and transmitting severe strains of the virus. Evidence is presented that gynoparae and males of R. padi are involved in the autumn spread of BYDV and that three further aphid species, Anoecia corni, Metopolophium albidum and M. frisicum are BYDV vectors. The use of live and continuous trapping techniques in forecasting BYDV epiphytotics is discussed.     

The evolution of two west African populations

Summary The identification of genetically coherent populations is essential for understanding human evolution. Among the culturally uniform ethnic groups of west Africa, there are two geographically distinct populations with high frequencies of sickle-cell hemoglobin (HbS). Although the HbS mutation in each group is found on distinguishable chromosomes 11, these populations have been assumed to be parts of a single population. Analysis of mitochondrial DNA (mtDNA) in these populations demonstrated that the two populations identified by alternative chromosomes 11 bearing HbS have distinct distributions of mitochondrial genotypes, i.e., they are maternally separate. These studies also showed that, contrary to expectation, the mtDNA of some individuals is heteroplasmic. For nuclear loci, a comparison of the frequency of alternative alleles established that these populations are genetically distinct. Both the mitochondrial and nuclear data indicate that these populations have been separate for approximately 50,000 years. Although HbS in the two populations is usually attributed to recent, independent mutations, the duration of the separation and the observed geographic distribution of the population allow for the possibility of an ancient origin of HbS. Assuming an ancient mutation and considering the known biogeography, we suggest that HbS protected selected populations from malaria in rain forest refuges during the most recent ice age.Offprint requests to: O.C. Stine     

Evaluation of relative fertility of cryopreserved goat sperm

This study was designed to compare differences in the in vivo fertility of cryopreserved goat semen assessed by heterospermic insemination with differences in in vitro analyses. Five groups of does were inseminated with mixed frozen-thawed semen from different pairs of bucks. The percentage of offspring sired by each buck in the pair was compared with the relative ability of spermatozoa from that frozen-thawed ejaculate to penetrate zona-free hamster ova, relative post-thaw acrosomal integrity, ability to undergo an acrosome reaction during in vitro capacitation, and assessments of sperm motility. In 4 of the 5 different insemination pairs, the ratio of offspring born was other than 1:1. Acrosomal integrity, ability of spermatozoa to undergo an acrosome reaction, and parameters of sperm motility were not correlated with differences in relative fertility in this experiment using ejaculates from fertile bucks. The ability of spermatozoa to fuse with the oocyte plasma membrane was highly correlated with relative in vivo fertility (R(2) = 0.78, P = 0.04). This suggests that fusion with the oocyte plasma membrane is an event in the fertilization process in which significant variation exists among fertile bucks. Assessment of ability of spermatozoa to fuse with zona-free hamster ova may contribute to analysis of post-thaw fertility of frozen-thawed buck semen.     

Y chromosome lineages in men of west African descent

The early African experience in the Americas is marked by the transatlantic slave trade from ～1619 to 1850 and the rise of the plantation system. The origins of enslaved Africans were largely dependent on European preferences as well as the availability of potential laborers within Africa. Rice production was a key industry of many colonial South Carolina low country plantations. Accordingly, rice plantations owners within South Carolina often requested enslaved Africans from the so-called "Grain Coast" of western Africa (Senegal to Sierra Leone). Studies on the African origins of the enslaved within other regions of the Americas have been limited. To address the issue of origins of people of African descent within the Americas and understand more about the genetic heterogeneity present within Africa and the African Diaspora, we typed Y chromosome specific markers in 1,319 men consisting of 508 west and central Africans (from 12 populations), 188 Caribbeans (from 2 islands), 532 African Americans (AAs from Washington, DC and Columbia, SC), and 91 European Americans. Principal component and admixture analyses provide support for significant Grain Coast ancestry among African American men in South Carolina. AA men from DC and the Caribbean showed a closer affinity to populations from the Bight of Biafra. Furthermore, 30-40% of the paternal lineages in African descent populations in the Americas are of European ancestry. Diverse west African ancestries and sex-biased gene flow from EAs has contributed greatly to the genetic heterogeneity of African populations throughout the Americas and has significant implications for gene mapping efforts in these populations.     

Polymorphism of the prolactin gene and its effect on fiber traits in goat

The prolactin gene (PRL) is a potential candidate gene for the goat cashmere traits in markerassisted selection. Thus, the aim of this study was to detect PRL gene polymorphism and its association with fiber traits in 200 Raini cashmere goats native to the south-east of Iran. A 196-bp fragment encoding exon 5 within the goat PRL gene was amplified using PCR specific primers. The amplification products were subjected to the single stranded conformation polymorphism (SSCP) analysis. Three different SSCP banding patterns (CC, AC, and AA) were observed in exon 5 of the caprine PRL gene. The pattern frequencies for CC, AC, and AA were 0.39, 0.38, and 0.23 and frequencies of the A and C alleles were 0.42 and 0.58, respectively. The genotypic distributions did not deviate from the Hardy–Weinberg equilibrium (P > 0.05). The number of observed alleles, number of effective alleles, expected heterozygosity, observed heterozygosity, mean of heterozygosity, expected homozygosity, observed homozygosity, Nei’s index and Shanon’s index were 2.0, 1.9, 0.48, 0.38, 0.48, 0.51, 0.61, 0.48, and 0.68, respectively. Results of association between genotypes and fiber traits indicated that the CC genotype had the highest fiber length compared with the AA and AC genotypes (P > 0.05) while there was no significant association between the PRL gene genotypes and fiber diameter. These results imply that the PRL gene polymorphism can be used as a molecular marker to improve fiber production without a negative effect on fiber diameter.     

Multi-trait mimicry and the relative salience of individual traits

Mimicry occurs when one species gains protection from predators by resembling an unprofitable model species. The degree of mimic–model similarity is variable in nature and is closely related to the number of traits that the mimic shares with its model. Here, we experimentally test the hypothesis that the relative salience of traits, as perceived by a predator, is an important determinant of the degree of mimic–model similarity required for successful mimicry. We manipulated the relative salience of the traits of a two-trait artificial model prey, and subsequently tested the survival of mimics of the different traits. The unrewarded model prey had two colour traits, black and blue, and the rewarded prey had two combinations of green, brown and grey shades. Blue tits were used as predators. We found that the birds perceived the black and blue traits to be similarly salient in one treatment, and mimic–model similarity in both traits was then required for high mimic success. In a second treatment, the blue trait was the most salient trait, and mimic–model similarity in this trait alone achieved high success. Our results thus support the idea that similar salience of model traits can explain the occurrence of multi-trait mimicry.     

A novel genetic variant of the goat Six6 gene and its association with production traits in Chinese goat breeds

We looked for novel genetic variations within the Six6 gene by PCR-SSCP, DNA sequencing and forced RFLP-PCR and estimated their associations with production traits in 2132 goats of eight indigenous Chinese breeds. A novel single nucleotide polymorphism (NM_001104993.1: g.232T>C) within the goat Six6 gene was identified. The frequencies of allele "C" varied from 0.8621 to 1.000, which were in Hardy-Weinberg equilibrium. Genotype and allele frequencies were found to be significantly different in the breeds. Association analysis revealed a significant relationship between genotypes and cannon circumference in Hainan black goats (P = 0.047); adult individuals with genotype CT showed higher cannon circumference than those with genotype CC. Another significant association of genotypes with five-year-old fiber length was found in Inner Mongolia white cashmere goats (P = 0.002). In addition, individuals with genotype CT had longer fiber length than those with genotype CC. The data revealed that the Six6 gene positively affects growth traits and cashmere traits. Polymorphism of Six6-PstI could be useful as a DNA marker for goat breeding and genetics via marker-assisted selection.     

Incidence of thermoduric psychrotrophs in milk produced in the west of Scotland

Thermoduric psychrotrophs were found in 27.2% of milk samples collected from 1040 farms in the west of Scotland. Of the micro-organisms isolated 85.8% were identified as belonging to the genus Bacillus and 9.9% were assigned to the coryneform group. Bacillus cereus occurred most frequently and B. licheniformis and B. coagulans also occurred in significant numbers.     

Considerations on the evolution of qualitative multistate traits

Simple models for the evolution of qualitative multistate traits are considered, in which the traits are permitted to evolve in time-dependent versus speciation-dependent fashion. Of particular interest are the means and variances of distances for these traits in evolutionary phylads characterized by different rates of speciation, when alternative characters are neutral with respect to fitness, and when the total number of observable characters is limited to small values. As attainable character states are increasingly restricted, mean distance (D) in a phylad decreases, regardless of whether evolution is a function of time or of rate of speciation. The ratio of mean distances in species-rich and species-poor phylads of comparable evolutionary age (D_R/D_P) remains near one when differentiation is proportional to time, even when attainable character states are severely restricted. D_R/D_P also nears one as a result of restricting character states when differentiation is proportional to rate of speciation, but the effect is not severe unless the number of character states is very small and the probability of change per speciation very large. These and other results are discussed with reference to available data sets on qualitative multistate traits.     

Investigation of individual heterozygosity correlated to growth traits in Tongshan Black-boned goat

Ten single nucleotide polymorphisms were used for genotyping of 176 Tongshan Black-boned goats, which are Chinese indigenous goat colony for meat production. The average individual heterozygosity was 0.292. To assess the correlations between individual heterozygosity and growth in Tongshan Black-boned goat individuals, and the potential of using individual heterozygosity as an indicator of growth, the data of growth traits, including body weight, height at withers, body length, chest girth and cannon circumference, were collected. Significant correlations were observed between individual heterozygosity and body weight, height at withers, body length, heart girth, cannon circumference (P < 0.05). All the significant regression showed positive slope with R square values ranged from 0.0251 to 0.0368. These data suggests that individual heterozygosity is positively correlated with growth traits in Tongshan Black-boned goat individuals and associative overdominance may affect Tongshan Black-boned goat growth significantly. Therefore it is possible to use individual heterozygosity as an indicator of growth. Our results also provide a strong support to the overdominance hypothesis.     

Flavones and isoflavones from the west African Fabaceae Erythrina vogelii

The CH(2)Cl(2)/MeOH extract of the stem bark of Erythrina vogelii (Fabaceae) from Nigeria has yielded two novel isoflavones, 7,4'-dihydroxy-8-(gamma,gamma-dimethylallyl)-2'zeta-(4'-hydroxyisopropyl)dihydrofurano[1',3':5,6]isoflavone (vogelin H) (1) and 7,4'-dihydroxy-8-[(2'zeta,3'-dihydroxy-3'-methyl)butyl]-2',2'-dimethyl-3',4'-dehydropyrano[1',4':5,6]isoflavone (vogelin I) (2), a novel flavone, 7,4'-dihydroxy-2',2'-dimethyl-3',4'-dehydropyrano[1',4':5,6]flavone (vogelin J) (3), and eight known flavonoids.